This is something I always wondered about: when I leave my charger plugged on the wall socket but not charging anything, is it still consuming energy?
Some notebook chargers have a led that is always on, so I guess it's consuming at least a bit. But what about Apple chargers? I want to leave my iPhone and iPad chargers always plugged under my desk (so I can just connect my device when I want to charge) but I'm worried they shouldn't be plugged all the time.